Ab initio study of the identity of the reaction product between carbon cluster (C3) and water in cryogenic matrixes

Abstract

Geometry optimization, energy calculation, and ab initio vibrational analysis were carried out on different conformers of singlet and triplet hydroxyethynylcarbene and 3-hydroxypropadienylidene. They are probable products of the reaction C{sub 3} + H{sub 2}O. Theoretical methods used include restricted Hartree-Fock, unrestricted Hartree-Fock natural and orbital-complete active space, and Moller-Plesset perturbation theory. By comparing the calculated harmonic frequencies (empirically scaled by 0.9) with observed FTIR frequencies of the product of the reaction C{sub 3} + H{sub 2}O in cryogenic matrices, it appears likely that the product is singlet 3-hydroxypropadienylidene instead of the previously proposed hydroxyethynylcarbene. 28 refs., 3 figs., 4 tabs.